Method and apparatus for producing crimped synthetic yarn



July 3, 1962 H. ENNEKING 3,

METHOD AND APPARATUS FOR PRODUCING CRIMPED SYNTHETIC YARN 3 Sheets-Sheet 1 Filed July 7, 1960 T-K W V5 m m w k 1477 W/YEYS July 3, 1962 H. ENNEKING 3,

METHOD AND APPARATUS FOR PRODUCING CRIMPED SYNTHETIC YARN Filed July 7. 1960 1 3 Sheets-Sheet 2 I IN VEN TOR. flE/hf/CH {wax/HG BY AFTOPWE/S y 3, 1962 ENN ING 3,041,813

METHOD A APPARA FOR DUCING CRIMPED SYNTHETIC Y Filed July 7, 1960 3 Sheets-Sheet f5 IN VEN TOR.

Ham/@014 [w/s ma- United States Patent Ofitice 3,041,813 Patented July 3, 1962 METHOD AND APPARATUS FOR PRODUCING CRIMPED SYNTHETIC YARN Heinrich Enneking, Wattwil, Switzerland, assignor to Heberlein Patent Corporation, New York, N.Y., a corporation of New York Filed July 7, 1960, Ser. No. 41,340 Claims priority, application Switzerland July 9, 1959 Claims. (Cl. 57-34) This invention relates to the treatment of yarn, and more particularly, to a method and apparatus for the production of an improved crimped synthetic yarn. especially a crimped yarn having reduced stretchability.

Heretofore, it has been known to produce crimped synthetic yarns of reduced stretchability by a method involving at least two steps. to wit; temporarily highly twisting the yarns by means of a false twisting device and heat setting the yarns in the highly twisted condition, and then untwisting and stretching out the yarns and subjecting them to a second heat setting in this untwisted, stretched-out condition.

In accordance with the prior art, different setting elements were used for the first and second heat settings of the yarns, with the result that considerable difficulty was experienced in maintaining the relative temperatures of the setting elements, and these temperatures often varied. For example, a downward change in temperature of the first setting element might coincide with an upward temperature change of the second setting element with the Overall temperature difference being additive and having a very unfavorable influence on the quality of the yarn.

I have conceived a surprisingly simple way in whicl to carry out the entire treatment with but a single ljeat setting element.

As a particular feature of my invention, the aforementioned method is characterized in that the yarn is conveyed via a restraining point, then in close engagement over a heated contact surface, through the twister of a false-twisting device to another restraining point, and then via the same contact surface between two restraining points, and to a further restraining point. The yarn preferably travels in opposite directions during its passages over the heated contact surface.

As another feature of the invention, there is provided apparatus for carrying out the aforementioned method comprising a yarn feeding device, a conveying device, a heatable contact surface for the moving yarn, and a false twisting device positioned between such heatable surface and the yarn conveying device. Another yarn conveying or winding device is also provided for the yarn returning from the first conveying device over the same contact surface.

A particular advantage of the invention resides in the fact that since the same contact surface or setting element is used for both settings, any temperature variations always occur similarly in both settings. Thus, possible variations in temperature do not so unfavorably influence the ultimate product as in the prior art where different setting elements are employed.

The present invention is particularly suitable for the treatment of polyamide yarns, for example, polyhexamethylene adipamide or a polymerizate of E-caprolactam, as well as polyester yarns. for example, polyethylglycol terephthalate.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood. and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be de- 2 scribed hereinafter and which will form thesubject of the claims appended hereto. Those skilled in the art Will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as including such equivalent methods and constructions as do not depart from the spirit and scope of the invention.

A specific embodiment of the invention has been chosen for purposes of illustration and description, as shown in the accompanying drawings, wherein:

FIG. 1 is a diagrammatic end elevational view showing an embodiment of the invention;

FIG. 2 is a front elevational view of the embodiment of FIG. 1;

'FIG. 3 is an end view illustrating in detail a portion of the apparatus shown in FIGS. 1 and 2;

FIG. 4 is a detail view of a brake mechanism illustrated in FIGS. 1 and 2;

FIG. 5 is a perspective view illustrating details of a yarn guide shown in FIGS. 1 and 2;

FIG. 6 is a fragmentary cross-sectional view through a portion of the yarn guide of FIG. 5;

FIG. 7 is a vertical sectional view through a roller of the embodiment of FIGS. 1 and 2, illustrating related parts in operating position in solid lines and at inoperative position in broken lines; and

FIG. 8 is a front view of the mechanism of FIG. 7.

Referring now to the drawings in detail, and more particularly to FIGS. 1 and 2 thereof, there is shown a device such as a cop 10 for supplying yarn to be treated. The yarn Y travels through a brake mechanism 11 to a large roller 12 of a double roller assembly 13, and is wound around the roller 12 several times by way of an auxiliary roller 14. The roller assembly 13 forms a yarn restraining point, referred to for convenience as the first such point. Roller 12 is rotated by contact with a friction drive shaft 15. Between this first restraining point and a yarn conveying device comprising a roller 17, constituting a second restraining point, there is provided an arched heatable contact surface 19. Actually the contact surface 19 is a surface on a slightly arched plate 20. The contact surface is preferably about 600 mm. long and formed of metal, desirably a non-corrosive metal, for example, the contact surfacemay be chromium plated. The plate 20 may conveniently be heated by an electrical resistance heater (not shown).

A false twisting device 21 is provided between the contact surface 19 and the second restraining point. This false twisting device may, for example, be of the type shown and described in Letters Patent No. 2,863,277 dated December 9, 1958, and is preferably disposed at a distance of about 200 to 300 mm. from the contact plate so that after leaving surface 19 the yarn passes through a correspondingly long air zone, where it cools somewhat until it reaches the twister 21. From the roller 17, which is driven by a friction drive shaft 16 and around whichit is again wound several times by way of an auxiliary roller 22, the yarn Y travels via a pig-tail guide 24 onto the surface 19 at a predetermined point and firmly engages the latter over the length of the distance X. The yarn guide 24 may, if desired, be mounted directly on the plate 20, as shown.

In order to adjust the intensity of the second heat treat ment of the yarn. the guide 24 is adjustable: so that it is possible to alter the length of the distance X along which the yarn Y is in contact with the surface 19 as it moves downwardly, as viewed in FIGS. 1 and 2. The yarn may thus contact the contact surface 19 along its entire length in both directions. or as the yarn passes over the contact surface the second time, the distance X may be but a portion of the total length of. the surface 19. Subsequently, the yarn 11 travels over a guide 25 and onto a sm-ill roller 26, which with the roller 12 forms the double rol er assembly 13 already mentioned; the yarn being wound about the roller 26 several times, by means of an auxiliary roller 27 mounted on the same shaft as the auxiliary roller 14. This roller 26 comprises the third restraining point. The yarn may be guided by the auxiliary roller 14 and guides 28 and 29 to a winding device 30.

It should be noted that the peripheral velocity of the roller 17 may be varied in relation to the peripheral velocity of the roller 12 by a suitable variable drive (not shown).

Turning now to FIG. 3, it will be seen that the double roller assembly 13 and the auxiliary rollers 14 and 27 may conveniently be mounted on the same supporting bracket 31. Each such roller comprises a multi-grooved wheel. The rollers 14 and 27. although mounted on the same shaft 32 may rotate independently of one another, while the rollers 12 and 26 may be formed integral with one another as shown, since they rotate together.

FIG. 4 illustrates details of the brake 11 which comprises a stationary shaft 34 having a portion of its length threaded as at 35 so that a collar 36 mounted thereon may be adjusted lengthwise of the shaft. The free end of the shaft carries a nut 37 and a sleeve 39 upon which are mounted a pair of friction discs 40 and 41 between which the yarn Y passes to be tensioned. with a spring 42 acting between the collar 36 and the disc 41 to urge the latter towards the disc 40.

As shown in FIGS. and 6, the pig-tail guide 24 is formed of a length of wire having at least a single complete convolution at a free end and looped or folded back at its other end as at 43, by which means it may be adjustably clamped to a block 44 by a clamping screw 45. It will be seen that the block 44 is formed with several slots 46 (FIG. 5) extending longitudinally thereof by which the block itself may be adjustably mounted on the arched plate 20. or the machine frame. it convenient. The pig-tail may thus be adjusted longitudinally over a rather substantial range so as to alter the length of the distance X (FIG. 1) along which the yarn is in contact with the surface 19 in its excursion between the second and third restraining points.

Referring now to FIGS. 7 and 8, there are shown details of mounting of the rollers 17 and 22. A U-shaprd bracket 47 is supported on the machine frame and has similar recesses formed in each arm and opening outwardly thereof, as at 49. A rocker 50 which may also be U-shaped is disposed within the arms of the bracket 47 and is supported for pivotal movement by pins 51 seated in the recesses 49. To provide the rocker 50 with a toggle action relatively to the bracket 47, a toggle spring 52 is connected at its ends to transverse bars 54 and 55 carried by the bracket 47 and the rocker 50, respectively. A bracket or plate 56 is conveniently secured to the rocker 50 for movement therewith between the positions illustrated in FIG. 7; and this plate in turn supports the roller 17 and the auxiliary roller 22. Thus, it will be seen that the roller 17 may be shifted into active position with an enlarged portion thereof against the surface of the friction drive shaft 16, or into inactive position out of contact with the drive shaft. As shown in FIG. 8, the roller 22 may be cocked relatively to the roller 17 for assuring the maintenance of the turns of yarn in the respective grooves of rollers 17 and 22.

It will be understood that the roller assembly comprising the roller 12 and the auxiliary roller 14 may be shiftable relatively to the friction drive shaft 15, and that structure similar to that described in connection with the roller 17 and the auxiliary roller 22 may be employed for this purpose.

The diameter of the roller 12, for example, may be 100 mm. and that of the roller 26, 91 mm., while that of roller 17 may be 97 mm. By so dimensioning the respective rollers the yarn tension between rollers 17 and 26 is about 0.005 to 0.05 g./ den. The double roller assembly 13 is so constructed that the smaller roller 26 can readily be replaced with one of a different diameter. In order,

for example, to obtain a yarn tension of 0.05 to 0.5 g./,

den., between the rollers 17 and 26, a roller 26 of a diameter of mm. may be used.

Example I Yarn Y consisting of .34 continuous filaments of polyhexamethylene adipamide and having a titer of .100 den. is treated with the aid of the apparatus illustrated in FlGS. l to 8.

The roller 12 of the double roller assembly is driven at a peripheral velocity of 77 meters per minute, and the yarn thus arrives at the plate 20, which has a length of about 600 mm. in the direction of movement of the yarn and a surface temperature of about 230 C. Prior to reaching the twister 21, the yarn traverses an air zone which is 200 to 300 mm. long. The twister has a speed of 200,000 r.p.m. Subsequently, the yarn is turned several times around the roller 17 by means of the auxiliary roller 22, the roller 17 having a peripheral velocity of 75 meters per minute. The yarn is then led by the guide 24 back to the contact surface 19. The yarn guide 24 is so adjusted that during the second passage of the yarn in contact with the surface 19, the distance X is about 400 mm. The roller 26 of the double roller assembly 13 receives the yarn by way of the guide 25 and has a peripheral velocity of 70 meters per minute so that the yarn tension between rollers 17 and 26 is about 1 to 2 g. The yarn produced in accordance with this example has a crimping contraction of about 25%.

The crimping contraction is determined as follows: Prior to determining the crimping contraction, the crimp of the yarns first must be fully developed. Of the material which is wound on cross bobbins in a tensioned condition. five strands of eight circumferences should be unwound (preferably 8 meters or 8 yarns), tension being maintained so that the yarn is stretched, say about 0.1 g./den. These strands, which may be sized or unsized, are then treated in untensioned condition for ten minutes in distilled water at 60 to 70 C., carefully centrifuged, and dried in untensioned condition. To carry out the measuring, the thus decrimped strands are dipped for 30 seconds in water at 60 C. containing 2 g. per liter of a conventional wetting agent, until they are quite Wet. The strands are then hung on a hook, weighted in wet condition with 0.2 g./den., care being taken that the yarn strands should hang completely smoothly. After the strands are thus weighted for one minute, the lengths of the wet stretched strands are measured. The weights are then removed and the strands dried at 50 to 60 C. After cooling for one hour in an air conditioned chamber, the strands are weighted with 0.002 g./den., and their lengths measured after one minutes weighting. From the measurings, the crimping contraction is calculated according to the following formula:

100- Z-100]==pereent crimping contraction where:

2a=a +a +a +a +a =sum of the individual measurings at 0.2 g./den.

Eb=b +b +b +b +b =sum of individual measurings at 0.002 g./ den.

Example 11 The roller 12 of the double roller assembly 13 is driven at a peripheral velocity of 65 meters per minute and the plate is heated to a surface temperature of about 200 C. The peripheral velocity of the roller 17 is 63 meters per minute. The yarn guide 24 is so adjusted that the distance X is about 300 mm. The roller 26 has a peripheral velocity of 59 meters per minute so that the yarn tension between the rollers 17 and 26 is about 1 to 2 g. The yarn produced in accordance with this example has a crimping contraction of about l Exampl z III A yarn consisting of 20 Continuous fibers of E-caprolactam polymerizate with a titer of den. is treated with the aid of the apparatus illustrated in FIGS. 1 to 8 and as described in Example I, but with the following modifications:

The roller 12 of the double roller assembly 13 is driven at a peripheral velocity of meters per minute and the plate 20 is heated to a surface temperature of about C. The peripheral velocity of the roller 17 is;63 meters per minute. The roller 26 has the same diameter as the roller 12 so that its peripheral velocity is also 65 meters per minute and thus the yarn tension between the roller 17 and the roller 26 is about 15 g. The arn produced in accordance with this example has a crinping contraction of about 25%.

From the foregoing description of a specific embodiment it will be seen that the present invention provides a method whereby crimped synthetic yarns of reduced stretchability are produced by a method involving but a single step characterized in that the yarn is conveyed between two restraining points over a heated contact surface. and through a false twister, and then in the opposite direction over the same contact surface to a third restraining point. Apparatus for carrying out the aforementioned method is also provided.

In its broadest aspect the present invention intends the use of the same heated contact surface for both of the heat setings to which a yarn is to be subjected in the production of a crimped synthetic yarn product. It also intends that in one of its passages over the heated contact surface the yarn shall contact at least a portion'of that surface. While in the specific embodiment described above in detail the yarn travels in opposite directions during its passages over the heated contact surface, it is quite obvious that it might be so directed as to pass in the same direction in the process specifically illustrated or in another yarn treating process. For example, without departing from the spirit of this invention roller or guide means might be provided adjacent the first restraining point to receive the yarn directly, without passage through guide 24, from auxiliary roller 22 and direct the same over the heated contact surface in the same direction as its first passage. Guide means 24 would then be employed to regulate the distance X during this second passage, and to direct the yarn toward a take-up device.

I believe that the operation and construction of my novel method and apparatus will now be understood,

and that the advantages of my invention will be fully appreciated.

I claim:

1. Apparatus for producing fully synthetic crimped yarn of reduced stretchability, consisting essentially of means for feeding yarn to be treated and constituting a first restraining point, yarn conveying means constituting a second restraining point, a heatable contact surface disposed between said first and second restraining points and over which the yarn is adapted to move in passing from said first to said second restraining points, a false twisting device between said contact surface and said second restraining point, a third restraining point so disposed that the yarn in passing between the second and third restraining points again passes over said contact surface, and an adjustable yarn guide so positioned relative to the heatable contact surface as to control the length of contact of the yarn with said heatable surface during its second passage thereover.

2. Apparatus in accordance with claim 1, in which the heatable contact surface is arched.

3. Apparatus as set forth in claim 1, wherein the first and third yarn restraining points comprise a double roller assembly consisting essentially of a first pair of rollers of different diameters mounted for simultaneous rotation on a common shaft and means for driving said rollers, and a pair of cooperating rollers mounted for independent individual rotation on a second shaft, one of said first rollers and one of said cooperating rollers constituting one yarn restraining point and the other of said first rollers and cooperating rollers constituting another such restraining point.

4. Apparatus as set forth in claim 3 wherein the roller of larger diameter of the first roller pair and one of said cooperating rollers constitute the first yarn restraining point.

5. A method for producing fully synthetic yarn of reduced stretchability, which consists essentially of temporarily highly twisting the yarn, passing the yarn in highly twisted condition over a heated contact surface to set the twist therein, maintaining the temperature of said heated contact surface at desired yarn setting temperature, cooling and untwisting the heat set yarn, then passing the untwisted yarn over the same heated contact surface to thereby subject the same to a second heat treatment at substantially the same elevated temperature and so controlling the untwisted yarn in its passage over the heated contact surface that the same is in contact with said surface for a shorter period of time than i the highly twisted yarn.

References Cited in the file of this patent UNITED STATES PATENTS 2,624,934 Munson et al. Jan. 13, 1953 2,815,559 Robinson Dec. 10, 1957 2,864,229 Seem et al Dec. 16, 1958 2,921,358 Cox et a1. Jan. 19, 1960 FOREIGN PATENTS- 2l9,270 Australia Dec. 5, 1958 807,516 Great Britain Ian. 14. 1959 

